Journal of Entomology and Zoology Studies 2016; 4(6): 121-126

E-ISSN: 2320-7078 P-ISSN: 2349-6800 Captive breeding and seed production techniques JEZS 2016; 4(6): 121-126 © 2016 JEZS of Endangered Giant River Received: 17-09-2016 Accepted: 18-10-2016 seenghala

Md. Ekramul Hasan Department of Fisheries Biology and Genetics, Md. Ekramul Hasan, AK Jilani Chowdhury and Md. Golam Sarwer Agricultural University, Mymensingh, Bangladesh Abstract A study was conducted to observe the breeding and seed production techniques of endangered giant river AK Jilani Chowdhury catfish, , locally known as “guizza air’’. In this study, a total of 60 pairs of adult guizza Aqua Services Department, Agro air (850-1500 g) were collected from the Brahmaputra river-basin and floodplains in Mymensingh region Vet Division, Square Pharmaceuticals Limited, and stocked in a 40 decimal pond with 2.5-3 feet depth three months before the onset of the breeding Dhaka, Bangladesh season. Hatchlings gradually started to consume zooplanktons available in the spawning pond and no artificial feeds were used. Fry numbering 50,280 with a mean ± SD length and weight of 1.91 ± 0.24 cm Md. Golam Sarwer and 0.25 ± 0.07 g, respectively were collected by repeated netting with mosquito net from the spawning Department of Fisheries and pond after 15 days of spawning. The fry were then stocked at 1000 fry/dec in two earthen nursery ponds Marine Science, Noakhali Science having area of 20 and 30 decimal with an average depth of 3 feet. Fry in two nursery ponds were reared and Technology University, with commercial nursery feed for the first 14 days and pre-starter feed during days 15-28. The water Noakhali, Bangladesh temperature in the nursery ponds was ranged from 30.53 ± 0.71 to 32.85 ± 0.49 oC during nursing. The values of dissolve oxygen (DO) and pH ranged from 6.50 ± 0.41 to 4.27 ± 0.71 ppm and 7.8 ± 0.62 to 7.2 ± 0.47, respectively. The final average length and weight of the fingerlings were 6.26 ± 0.21 cm and 2.55 ± 0.08 g, respectively after four weeks of nursing. The survival rate of fry was 63% with a net production was 630 fry/dec. It can be concluded that the captive breeding and seed production techniques of S.

seenghala described here is an important step in conservation and pond culture of the endangered S.

seenghala.

Keywords: Captive breeding, seed production techniques, endangered Sperata seenghala etc

1. Introduction Captive breeding of indigenous and exotic aquaculture species for seed production has been a common practice in Bangladesh since 1967 [3]. Most hatcheries rear their own brood stock and usually do not recruit brood stock from natural sources (rivers) or exchange breeders between farms. Each hatchery therefore, can be considered as an isolated, self-sustaining and [9] genetically closed unit . It is established that in genetically closed hatchery systems, potential selective pressures exerted on finite and often small culture populations by various farm management practices such as the selection of founder stock, number of breeders maintained, method of replenishing brood stock, stocking density, feeding regime etc. can result in indirect or negative selection, inbreeding and genetic drift [9].

One of the important bagrid catfish is the giant river catfish Sperata seenghala, locally known as “guizza air” and was once available in rivers, floodplains, inundated swamp fields, ditches, canals and other freshwater areas throughout , , , and Bangladesh [11]. This species is also found in the Chalan Beel, Choto Jamuna River, Halti Beel [10]. It has been considered as one of the most admired edible fish among indigenous catfish

species due to good taste and high market demand. It is commercially fished for human consumption as well as being a popular game fish with a reputation for being a good fighter when hooked. It can be distinguished from other sperata species by its spatulate, blunt snout, relatively short barbels and mouth that is only 1/3 as wide as the head is long [12]. The fish is carnivorous and predatory in nature, subsists on various types of organisms such as fish, frogs, Correspondence [15] Md. Golam Sarwer snakes, insects, earthworms, tadpoles, crustaceans and debris . Food at different life stages: Department of Fisheries and insects and fish-fry (fry); water fleas, fish-fry, insects and smaller fingerlings (fingerling); Marine Science, Noakhali Science Insects, tadpoles and fish (Adult) [18]. Gut content analysis of S. seenghala indicate that the gut and Technology University, content consists of about 80-90% is food matter of which the major food components Noakhali, Bangladesh ~ 121 ~ Journal of Entomology and Zoology Studies

are locally available weed fish species Puntius ticto, Chela drag netting, segregated and transferred into spawning pond. phulo, Ambassis nama. The percentage of animal matter in the diet is increased by 5-10% with increase in body size from 2.4 Rearing of broodstock and its management Small (20-25cm) to large (60-65cm) [4]. Fish were fed twice daily with supplemental feed at the rate of This fish usually spawns twice a year from May to July and 5–6% of the estimated fish biomass. The pond was fertilized from September to November in natural condition [15]. Early at biweekly intervals with cow dung (5 kg/dec) and urea and and developing stage oocytes were mostly observed during triple super phosphate (200 g/dec) to accelerate the primary April-May, maturing oocytes in June, and mature oocytes productivity of the ponds throughout the entire rearing. during July-August. Early and developing germ cells were mostly observed during April-May, gradually maturing in 2.5 Nursery pond selection and preparation June, and mature germ cells during July-August sections of Two ponds were selected for nursing of guizza air fry. The testes. The combination of ovarian and testicular histology areas of the selected two ponds were 20 and 30 dec, summarizes that S. seenghala breeds during late monsoon. It respectively with average depth of 2.5-3 feet. Deep ground is remarkable that, while many fish species from the water was collected and used for nursing guizza air fry. freshwaters start to breed with the first rain in the year, S. seenghala breeds in the late monsoon [1]. 2.6 Collection of fry from spawning pond This fishes are testy and have high market value. As a result, After 15 days of spawning, a total of 50,280 guizza air fry development of artificial propagation and mass seed were collected from the spawning pond by mosquito net. production techniques might create excellent livelihood After collection, the fry were transferred to prepared earthen opportunities for hatchery and nursery operators, fish farmers nursery ponds for four weeks of nursing. Fry having a (mean and traders. Steps should be taken to develop induced and ± SD) length of 1.91 ± 0.24 cm and weight of 0.25 ± 0.07 g, controlled natural breeding technique for small and medium taken from 20 randomly sampled individuals, were then scale seed production of S. Seenghala. Captive breeding and stocked in two nursery ponds. mass seed production techniques of S. seenghala should be developed to supply the seeds for commercial farming as well 2.7 Stocking and rearing of fry in nursery pond as to save the gene pools of these valuable species. Present A total of 50,000 fry were stocked at a rate of 1000 fry/dec in study was conducted to achieve following objectives: two nursery ponds. In nursery ponds, watering is done up to 3  To gain practical experience of captive breeding and seed ft depth and 100 g flour/dec is mixed with pond water. This production techniques of the giant river catfish S. flour results in growth of plenty of zooplankton which is very seenghala. essential for fry. After two days of fry stocking, 3 ml/dec  To increase seed production of S. seenghala through sumithion is added to the nursery pond water in order to kill scientifically improved nursing technique. haspoka.  To conserve the species S. seenghala through mass seed production. 2.8 Feeding of fry In nursery pond, blended eggs were supplied as first feed. Ten 2. Materials and Methods blended eggs are enough for 20 dec nursery ponds. Nursery 2.1 Study area and time feed was applied 3 times/day (morning, noon, evening). After The present research work was a study on captive breeding four weeks of nursing, fry attained the size of 6.26 ± 0.21 cm and seed production techniques of endangered giant river and 2.55 ± 0.08 g in length and weight, respectively which catfish started on March 2014 and it was conducted in the were ready for marketing. ponds located in the Desh Bondhu Hatchery of Mymensingh, Bangladesh and Nursery from April 2014 to August 2014. 2.9 Water quality monitoring Various water quality parameters such as temperature (oC), 2.2 Spawning pond preparation transparency (cm), dissolved oxygen (mg/L), pH, ammonia An earthen pond was selected for captive breeding of guizza nitrogen (mg/L) were recorded weekly between 9 am and 10 breeders. The area of the selected pond was 40 dec with 2.5-3 am throughout the experimental period. Water samples were feet depth. The experimental pond was prepared by using collected from spawning and nursing pond. All the water rotenone at the dose of 20 mg/L water for eradicating quality parameters were measured on the spot. unwanted fish species. Fertilizers were applied to increase the plankton density in pond water. Seven day after fertilization, 2.10 Methods for physical and chemical factors estimation the pond water became greenish with the abundance of The transparency of water was measured by a standard secchi phytoplankton and zooplankton and ready for brood stocking. disc fitted to a rope. Water temperature of the experimental For stimulating the natural propagation of guizza air, the ponds was recorded in Celsius (oC) by holding a Celsius spawning pond was supplied with fresh groundwater to thermometer under water for 1 minute. pH and DO were maintain a natural condition (e.g., temperature adjustment, determined by using portable pH and oxygen meter, water circulation, mate selection, sex stimulation, and respectively. courtship induction) for breeding. 2.11 Fry sampling 2.3 Collection of broods and stocking in the spawning Fifty individuals from each pond were sampled weekly until pond they attained the fingerling stage. Fish sampling was done to Broods were collected from the brood rearing pond of the adjust the feeding rate by measuring the weight of fish, to farm. A total of 60 pairs of adult guizza air (60 males and 60 observe the health condition and to keep the record of length females) weighing between 850 and 1500 g were collected and weight of fish. After recording the length and weight of three months before the onset of the breeding season. Brood the fry they again were released to the respective ponds. fish were collected from the brood rearing pond by repeated

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2.12 Growth study about 2 to 2.5 feet below the water surface during breeding For comparative growth study of fry for the research work, season. In the nests, one male was found with a female the following growth parameters were calculated and moving together randomly for certain time, closed to each analyzed. Survival rate, specific growth rate (%SGR), length other, nudge each other and become aggressive within a gain (LG) weight gain (WG), feed conversion ratio (FCR) limited area. This process was repeated several times until were calculated by using the following formula: spawning. The size of holes was differ from 1.5 to 2 feet in No. of total fry obtained diameter with 6 to 7 inch in depth where female laid eggs at 100 night during 4th week of June, 2014. Average water Survival rate = No. of total fry stocked temperature during spawning was 30.37 ± 0.58 oC. Fertilized Log eW  Log eW eggs hatched within 2-3 days. Following spawning, females 2 1  100 protected their nests and showed extreme parental care up to T  T SGR (%/ day) = 2 1 10 to 15 days. Near the end of and immediately after the yolk sack absorption females fed their young with their own skin Where, W1 = Initial body weight (g) at time T1 (day) and mucus. In the nest, females were found to lose their skin W2=Final body weight (g) at time T2 (day) Average length gain (cm) = Average final length (cm) - mucus and the color of the body changed from brownish back Average initial length (cm) and whitish to reddish. Hatchlings gradually started to Average weight gain (g) = Average final weight (g) - Average consume zooplanktons available in the spawning pond and no initial weight (g) artificial feeds were used. The total number of fry collected Average weight gain (g)/day at different week from the spawning of 60 pairs of S. seenghala was 50,280 = (838 fry/pair) with a mean ± SD length and weight of 1.91 ± Weight (g) in present week - Weight (g) in previous week 0.24 cm and 0.25 ± 0.07 g, respectively. After 15 days of spawning, fry numbering 50,000 were transferred to prepared Days of week earthen nursing pond for four weeks of nursing. Total feed used FCR Final body weight g Initial body weight g 3.2 Feed application rate To maintain proper growth rate of guizza air fry, it is 2.13 Harvesting necessary to apply appropriate type and amount of feed. To Fingerlings were collected from the nursery pond after four obtain desired seed production of guizza air fry feed should weeks. While collecting for sale, each fingerling length was contain 35% protein. In market, now a days, there are various about 6.26±0.21 cm and weight was 2.55±0.08 gm. complete types of feed available which contain higher amount of harvesting was done by seine net. protein. In this study, mainly two types of feed were used in different stages of nursing. Nursery feed (powder) was used 2.14 Cost and profitability analysis for first two weeks and floating Pre-starter feed was used for Analysis of different cost throughout the nursing period was next two weeks of nursing period. Based on the nursing done depending on data collected from the farm manager in period, the types of feed and feed application rate are given in order to determine the profitability and potentiality of guizza the following Table 1: air culture. These costs include several fixed and variable cost such as cost of pond preparation, price of seed and feed, labor Table 1: Types of feed and feed application rate in nursing of guizza cost, price of fertilizer, lime and water supply cost. Benefit- air fry cost ratiocan be calculated by using the following formula: Culture stage Nursing For 1 year tenure there is no discount factor, hence benefit Week 1st 2nd 3rd 4th cost ratio should be, Types of feed Nursery feed Pre-starter feed Artificial feed (kg) 14 33 50 75 Benefit-cost ratio = Feeding rate 14 12 (% of body wt) Present value of benefit FCR 0.70 1.32 1.67 1.88 Present value of cost for artificial feed

3. Results 3.3 Growth and production of fry The growth performance and production of giant river catfish During the nursing period, different growth parameters such Sperata seenghala and the water quality parameters obtained as the average length (cm), average weight (g), average daily in the present study are presented below: weight gain (g/day), specific growth rate (SGR%), survival rate (%), net production (number/dec) was observed. The net 3.1 Sperata seenghala spawning production (number/dec) of guizza air fry was 630 fry/dec. In the present study, spawning pairs of S. seenghala were The survival rate of guizza air fry was 63%. Different growth found to excavate holes (nests) at the edge of the pond dike at parameters of guizza air fry are given below in Table 2.

Table 2: Different growth parameters of fry during nursing period

Culture stage Nursing Week Initial (mean±SD)1st (mean±SD)2nd (mean±SD)3rd (mean±SD)4th (mean±SD) Average length(cm) 1.91±0.24 2.98±0.28 4.55±0.34 5.68±0.27 6.26±0.21 Average weight (g) 0.25±0.07 0.65±0.09 1.15±0.06 1.75±0.07 2.55±0.08 Average daily weight gain (g)/day 0.02±0.07 0.06±0.09 0.07±0.06 0.09±0.07 0.11±0.08 SGR (%) 0 13.65±0.09 8.15±0.06 5.99±0.07 5.38±0.08

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3.4 Water quality parameters The physico-chemical parameters like water temperature (oC), ammonia nitrogen (mg/L) were recorded weekly during the dissolved oxygen (mg/L), pH, water transparency (cm), and experimental period is presented below in Table 3.

Table 3: Weekly water quality parameters observed during nursing period

Week 1st (mean±SD) 2nd (mean±SD) 3rd (mean±SD) 4th (mean±SD) Temperature (oC) 32.85±0.49 32.38±0.67 31.78±0.42 30.53±0.71 Dissolved Oxygen (mg/L) 6.0±0.82 6.50±0.41 5.37±0.63 4.27±0.71 Transparency (cm) 37.84±2.02 32.67±2.08 29.17±1.89 24.34±1.26 pH 7.6±0.12 7.8±0.62 7.5±0.71 7.2±0.47 Ammonia nitrogen (mg/L) 0.0 0.19±0.02 0.41±0.04 0.68±0.02

3.5 Cost and profitability analysis BDT, total income was 3,78,000.00 BDT and benefit was There were different site of cost in the nursing period of 2,73,130.00 BDT. Benefit-cost ratio was 3.60. Total cost of guizza air. The total production cost of fry was 1, 04, 870. 00 production and profitability are given in the Table 4.

Table 4: Cost and profitability analysis of guizza air fry nursing

Expanses in production area Amount Cost (BDT)/unit Total cost (BDT) a. Management expanses 1. Pond lease cost (30+20) or 50 decimal 500.00/decimal 25,000.00 2. Labor cost (provides protection, feed supply, weed cleaning etc.) 1 person 5,000.00/month 5,000.00 3. Net dragging or doing horra 1 times 200.00/time 200.00 4. Water supply 2,000.00 5. Electricity 1,000.00 6. Others 2,000.00 Partial total 35,200.00 b. Cost of pond preparation 1. Pond repairement 10 labor 250.00/labor 2,500.00 2. Pond drying and removal of other fishes 1,500.00 3. Lime application 50 kg 20/kg 1,000.00 4. Cow dung 500 kg 0.5/kg 250.00 5. Fertilizer 20 kg 30/kg 600.00 6. Medicine 1,500.00 Partial total 7,350.00 c. Seed of guizza air 50,000 pieces 1.00/pc 50,000.00 d. Supplementary feed 172 kg 60.00/kg 10,320.00 e. Feed transportation and others 2,000.00 Total expanse (a+b+c+d+e) 1,04,870.00 Production & income i. Production of guizza air fry (63% survival rate) 31,500 pieces 12.00/piece 3,78,000.00 Total income 3,78,000.00 Actual income (total income-total expanse) 2,73,130.00 Benefit-cost ratio 3.60

4.1 Sperata seenghala spawning In the present study, a total of 60 pairs of S. seenghala breeders successfully spawned in earthen pond which was also reported by Rahman et al [15]. In their study, they found 30 pairs of S. seenghala breeders naturally spawned in earthen pond. In this study, a total of 50,280 fry (838 fry/pair) were collected from the spawning pond. Rahman et al. [14] found 300 and 762 fry/pair from the spawning of 10 and 30 pairs of S. seenghala, respectively which is more or less similar to the findings of present study. In the present study, average water temperature of spawning pond was recorded 30.37 ± 0.58 oC

Fig 1: Cost of guizza air seed production in different sector indicating quite favorable for breeding of S. seenghala is [16] similar with the findings of Sarker et al. for the breeding 4. Discussion of Chitala chitala in which breeding temperature was 29 ± 2.2 o The study showed the breeding, growth, specific growth rate C. In the present study parental care of female S. seenghala (SGR %) and survival rate of S. seenghala fry fed on the same was observed during larval development by protecting nest level of diets in the ponds having similar environmental and feeding their young with their own skin mucus. However, [6] conditions. However, many factors are related to the nursing Chonder reported that both male and female participate such as stocking density, production system, type and size of actively in parental care of C. chitala. rearing ponds, size of fish and quality and quantity of food [13]. 4.2 Growth performance In the present study, the stocking density was 1000 fry/dec ~ 124 ~ Journal of Entomology and Zoology Studies

during nursing of S. seenghala. Rahman et al. [14] observed generally expressed as the level of productivity of water body that the growth, survival, production and net benefits of S. and also indicates the presence or absence of plankton in a seenghala fry were inversely related to the stocking densities water body. In the present study, transparency ranged from of fingerlings. Growth in terms of length, weight and survival 24.34 ± 1.26 to 37.84 ± 2.02 cm which assumed to be the of fry was lower in this study. The causes might include suitable level. Wahab et al. (17) suggested that the competition for food and habitat due to higher number of fish. transparency of productive water should be 40 cm or less. pH The result of the present study is similar with the findings of is considered as an important factor in aquaculture and treated Rahman et al [15]. In the present study, maximum average as the productivity index of a water body. In the present weight was 2.55 ± 0.08 g obtained from the fry fed with study, pH was found to fluctuate from 7.2 ± 0.47 to 7.8 ± 0.62 nursery and pre-starter feed containing 33% and 30% protein and considered as suitable range for fish culture. The pH respectively. The observed result is in agreement with the value recorded from the experiment agreed with the findings report of Ali et al.(2) who tested the performance of different of Ali et al. [2] who found pH to range from 7.55 to 7.84, 7.05 diets containing 25, 30, 35, 40% protein in dry weight basis to 7.72, 7.51 to 7.91, 7.40 to 8.80, and 7.50 to 8.40, and reported that 35% protein is optimum in diet for respectively. The presence of ammonia in pond waters is commercial rearing of S. seenghala. In this study, the average normal due to natural fish metabolism and microbiological daily weight gain ranged from 0.02 ± 0.07 to 0.11 ± 0.08 decay of organic matter. The total Ammonia (NH3) g/day which is more or less similar to Rahman et al. [14] who concentration was found to vary from 0.0 to 0.68± 0.02 mg/L found that guizza air fry can achieve a rate of growth from during the study period which is similar with the findings of 0.01 to 0.07 g/day during nursing in earthen pond. The Rahman et al. [15] who recorded ammonia-nitrogen value to present result is in agreement with the report of Rahman et al. range from 0.01 to 0.82 and 0.203 to 0.569 mg/L, respectively [15] who reported that the average daily weight gain of and also more or less similar with Rahman et al [14] who snakehead fingerlings ranging from 0.02 to 0.09 g/day. The recorded ammonia- nitrogen value to range from 0.268 to SGR values of S. seenghala ranged from 5.38 ± 0.08 to 11.26 0.327 and 0.94 and 1.58 mg/L, respectively. ± 0.09% in this study. It is evident from the results of SGR values that, with the increase of age the values of SGR 4.4 Cost and profitability analysis decrease. This finding resembles the Medawars [12] fifth law In the present study, an economic analysis was performed to "the specific growth declines more and more slowly as the estimate the net profit from seed production of S. seenghala. organism increases in age". The SGR% value of S. seenghala The findings came up from the study that the production of S. fry in this study also shows the same trend. In this study, the seenghala was 630 fry/dec and per dec total return was FCR value ranged from 0.70 to 1.88 which is lower than Ali 7,560.00 BDT for the nursing period. Cost of production was et al. [2] who found that the FCR value of S. seenghala and 2,097.40 BDT per dec and the Benefit Cost Ratio (BCR) was Channa striatus to range from 2.02 to 2.15 and 2.71 to 2.87, 3.60. So, seed production of S. seenghala is profitable. Cost respectively. De Silva and Davy [7] reported that digestibility of fry, labor cost, feed cost, fertilizers and chemicals cost and plays an important role in lowering the FCR value by efficient nursing period included in the profit frontier had a significant utilization of food. However, the lower FCR value in the influence on profit of S. seenghala fry nursing in this study. present study indicates better food utilization efficiency. Rahman et al. [14] found BCR for S. seenghala fry nursing was Present study shows survival rate of S. seenghala fry was 4.23 in their study which is more or less similar to the present 63% which is lower than Rahman et al. [14] who found study. Rahman et al. [15] observed the BCR of tilapia culture survival rate of S. seenghala fry was 69.25% in their 56 days was 1.25 in his study of profit efficiency of tilapia experiment with artificial feed. Lower survival rate of S. monoculture in Trishal upazila of Mymensingh district. seenghala fry is achieved because of higher stocking density in the present study. Productions (gross and net) of guizza air 5. Conclusion fryfound in this study were 31,500 pieces and 630 pieces/dec. The result of present study clearly indicates that captive Rahman et al. [15] found a gross production of 112,500 to breeding of S. seenghala in natural condition is possible and 117,000 fingerlings ha-1 following the culture of snakehead fingerlings produced from the nursing can be used for rearing (Channa striatus) for two months at 150,000 fry ha-1 stocking to marketable size. Evidently, captive breeding program densities. Rahman et al. [14] observed that under the should be undertaken for species restoration and conservation. monoculture condition, the production of guizza air fry was As the fishes are testy and have high market value, 65,321 to 72,179 pieces ha-1 for two months at 100,000 fry ha- development of captive breeding and mass seed production 1 stocking densities. techniques might create excellent livelihood opportunities for hatchery and nursery operators, fish farmers and traders. The 4.3 Water quality parameters meteorological and hydrological conditions are suitable for In the present study, the water temperature ranged from 30.53 the breeding of this fish species. Biologically productive ± 0.71 to 32.85 ± 0.49 oC in the nursing pond. The result is natural water with controlled weed growth and rich more or less similar to Rahman et al. [15] who recorded phytoplankton, zooplankton and macro invertebrate fauna temperature to range from 26.0 to 35.0 oC, 22.0 to 34.0 oC, would be ideally suited for the growth of guizza air fish. The 24.2 to 32.0 oC and 28.60 to 31.90 oC, respectively. These results of the current experiment suggest that S. seenghala is a results agree well with the findings obtained by Rahman et al. suitable and potential species for captive breeding in small [15]. Dissolved oxygen (DO) in the present study was found to scale fish hatchery and commercial culture. vary from 4.27 ± 0.71 to 6.50 ± 0.41 mg/L in the nursery pond. DoF [8] suggested the suitable range of DO as 5.0 to 8.0 6. References mg/L. The concentration of dissolved oxygen in the present 1. Akhter T, Rashid H. Reproductive cycle of giant river study was also similar to the findings of Wahab et al. [17] who catfish Sperata seenghala from the Sylhet basin. recorded dissolved oxygen to range from 2.7 to 7.2, 4.0 to 7.0 Bangladesh Fisheries Research Forum, 5th Fisheries and 4.3 to 6.9 mg/L, respectively. Water transparency is Conference and Research Fair. 2012, 182.

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